Compatibility
7 expert answers on Compatibility. Practical guidance from a master gunsmith with 30+ years of experience.
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What Barrel Nut Thread Pattern Does My AR-15 Upper Receiver Use?
Standard AR-15 upper receivers use 1-3/16 x 16 TPI (threads per inch) barrel nut threads. This is a universal military s…
Can I Use the Same Bolt Carrier Group for Different AR-15 Calibers?
No, not always. A standard 5.56 NATO bolt carrier group works for 5.56, .223 Remington, .223 Wylde, and 300 Blackout bec…
What Are the Different AR-15 Handguard Mounting Systems?
The three main AR-15 handguard mounting systems are drop-in (two-piece) handguards that attach to the delta ring and fro…
What Buffer Weight Should I Use for My AR-15 Build?
Start with a standard carbine buffer (3.0 oz) for most builds. Move to an H buffer (3.8 oz) if your rifle is slightly ov…
Will Any AR-15 Upper Fit Any AR-15 Lower Receiver?
Yes, any mil-spec AR-15 upper receiver will fit any mil-spec AR-15 lower receiver. The takedown pin and pivot pin dimens…
What Thread Pitch Does My AR-15 Muzzle Use for Muzzle Devices?
Standard AR-15 barrels in 5.56 NATO and .223 Remington use 1/2 x 28 TPI (threads per inch) muzzle threads. AR-10 barrels…
Are AR-15 Triggers Universal? Will Any Trigger Fit My Lower?
Yes, virtually all AR-15 triggers are compatible with any mil-spec AR-15 lower receiver. The trigger, hammer, and discon…
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